In the field of outdoor power equipment, riding mowers are known for cutting large areas of grass. Such mowers typically comprise a frame carrying a prime mover and a cutting deck mounted to the frame. The frame is supported for rolling over the ground by a pair of front caster wheels and a pair of rear drive wheels that are driven in some fashion from the prime mover. The drive wheels are often independently drivable in forward and reverse to provide zero radius turn (ZRT) capability. An operator is carried on a seat provided on the frame and operates the drive wheels and steers the frame using various controls adjacent the seat.
As can be appreciated, the owner of such a mower has a substantial capital investment in the mower. Yet, in northern climates, the mower may not be used year round, but can sit idle during the winter. It would be desirable if the mower could effectively do double duty and be customarily used for winter snow removal operations. This would make the purchase of such a mower more cost effective and easier to justify.
Attempts have been made in the past to adapt a mower for snow removal by mounting a snowblower or snowplow on the front of the mower. If the snowblower is powered, a drive belt or other drive system would extend from the mower to the snowblower to power the snowblower. However, the basic drive system of the mower is not changed. In other words, the weight distribution and traction characteristics that were designed into the mower to give optimum performance as a mower are not changed merely by adding a snowblower or snowplow to the front of the mower.
The traction characteristics of a riding mower might work adequately on a relatively dry surface and allow the mower to push a snowblower or snowplow. But, these are not the surface conditions experienced when snow removal is needed. The ground surface then is normally snowy and/or icy. Thus, the tractive ability of a mower, particularly of a large riding mower carrying a seated operator, is not ideal or well suited for operating on such a slick surface.
Using a normal riding mower for snow removal operations often results in a snow removal product that does not perform well and that tends to lose traction. As mentioned above, the mower's traction system is not designed for snowy conditions. Moreover, when a snowblower or rotary brush or the like is added to the front of a mower, the added weight of this front mounted attachment tends to lift the drive wheels of the mower off the ground, particularly when the attachment is lifted up above the ground by some type of lift and lower system. In this situation where the rear drive wheels are lifted upwardly relative to the ground by the weight of the attachment, traction can be reduced so much that climbing a curb or driving the mower onto a trailer becomes very difficult or impossible.
Accordingly, dedicated, single purpose, tracked snow removal machines have been developed for clearing snow. The owner can purchase such machines for use in snow removal operations during the winter. However, this does not solve the problem of cost effectiveness. The snow removal machines sit idle during the summer, and the mower sits idle during the winter. Essentially, the owner must purchase and maintain two sets of equipment.
Thus, there is a need in the art for a product that would convert between a mower and a tracked implement and provide optimum traction and weight distribution in either form. This would be cost effective and yet give good operational results whether mowing or using the tracked implement for snow removal or some other non-grass mowing operation.
In using a machine of the type contemplated, whether in the mower or tracked implement form, it will often be necessary to climb small obstructions such as a curb. The operator will often drive the machine up over a curb or off a curb as the machine is transported from one area to the next. This presents various problems to a tracked implement. For example, as a tracked implement climbs a curb, some of the track support idlers or drive members will be up on top of the curb while others will still be on level ground. This will stretch or elongate the track and quickly cause the track to fail.
Tracked implements often solve the problem of track elongation by using idlers that are spring biased to accommodate the change in track length. However, this is a relatively complicated and costly track suspension system that is difficult to maintain and keep clear in winter operations. If a mower is to convert to a tracked implement, it would be desirable to have a simple, durable and effective way of solving the problem of track elongation.
Finally, in considering the operation of many known mowers of the type under consideration, the cutting deck is suspended from the frame of the mower to follow the contours of the ground independently of the mower. This is best done with a relatively light cutting deck. However, light cutting decks are not extremely durable and often wear quickly during operation.
One can attempt to improve the durability of a cutting deck by increasing the weight of the deck using thicker and stronger materials to form the deck. Such heavier decks, while more durable, tend to exhibit poorer ground following characteristics. For example, in the lowest or lower height of cut settings, such heavier decks will dig or plow into the ground despite using anti-scalp rollers, wheels or skids on the decks. This causes the cutting blades carried on the decks to scalp the turf. It would be desirable to have a relatively heavy cutting deck that still exhibits good ground following characteristics.